49 ST and High Altitude

Fig. 49 Air Injection System Operating Conditions (49 State/High Altitude):

Cold Engine:

The Air Suction Control Solenoid is on when:
1. Coolant temperature is above 40°C (104°F) but less than 74°C (165°F).
Vehicle speed is below 47 mph.
Engine speed 3,000 rpm (manual).
Engine speed 3,700 rpm (automatic).
AND
2. Vacuum switch A on.
AND/OR
3. Intake air temperature above 20.5°C (69°F).
Vacuum switch B off.

Warm Engine:

The Air Suction Control Solenoid is on when:
1. Coolant temperature above 74°C (165°F).
Vacuum switch B off.
Engine speed below 3,000 rpm
OR
Engine speed above 3,000 rpm (on delay 2 seconds).
AND
2. Vacuum switch A off.
AND/OR
3. Intake air temperature below 65°C (149°F).
OR
Intake air temperature above 65°C (149°F) and vehicle speed above 12.5 mph.